Authentication device, authentication method, and recording medium

ABSTRACT

The disclosure is detecting an authentication target who is moving in a predetermined direction in a video; inputting a first image in which an entire body of the target; calculating characteristic information from an image of the entire body in the first image, comparing the calculated characteristic information with characteristic information of the entire body stored in first memory that stores characteristic information of entire bodies of targets, and extracting candidate information of the targets from the first memory based on a first authentication result; inputting a second image in which an iris of the target; and comparing characteristic information of irises stored in second memory that stores the characteristic information of the irises of targets with characteristic information of an iris from the second image, calculating a verification score, executing second authentication on the target in the second image based on the verification score, and outputting an authentication result.

The present application is a Continuation application of Ser. No.17/279,237 filed on Mar. 24, 2021, which is a National Stage Entry ofPCT/JP2018/036424 filed on Sep. 28, 2018, the contents of all of whichare incorporated herein by reference, in their entirety.

TECHNICAL FIELD

The example embodiments relates to an authentication device or the likethat authenticates a target.

BACKGROUND ART

Personal authentication based on an individual difference of a livingbody (Biometrics-based authentication) has a lower risk of leakage andtheft than a password or the like created by a user. For this reason,there are increasing examples of introducing the personal authenticationbased on the individual difference of the living body to identify theindividual and confirm the right or for security protection. A personalauthentication technique based on the individual difference of theliving body has been known that uses fingerprints (Fingerprint), veins(Vein), faces (Face), irises (Iris), voices (Voice), or the like asbiometric information.

Among these, in face authentication and iris authentication, positions(face and eyes) of authentication targets are almost the same, andmulti-modal authentication in which the face authentication and the irisauthentication are combined has been developed (refer to cited documents1 and 2).

CITATION LIST Patent Literature [PTL 1] JP 2000-102524 A [PTL 2] JP2005-242677 A SUMMARY Technical Problem

There is a need for companies and organizations that operate commercialfacilities and large event venues to utilize walkthrough authenticationfor an entrance and exit management system in order to enhance securitymeasures and enhance convenience of the user side in entrance and exitmanagement of a large number of users. In the walkthroughauthentication, a living body (user) to be authenticated only walksthrough a predetermined section without stopping in front of anauthentication camera. As a result, authentication processing can beexecuted at high speed even if the number of users to be authenticatedis large and without making the user side conscious of theauthentication processing. When the face authentication and the irisauthentication are applied to the walkthrough authentication incombination as the multi-modal authentication, it is preferable becauseauthentication data can be collected only by performing imaging using acamera without having contact with the users.

However, because the user moves in the walkthrough authentication, atime period spent on the authentication is limited. Specifically, a timeperiod from a time when the user enters an authentication gate entranceand images an image to be used for authentication (authentication starttime) to a time when the user ends the authentication and passes throughan authentication gate exit (authentication completion time) is limitedto about several seconds. Therefore, if the positions of theauthentication regions are close to each other as in the combination ofthe face authentication and the iris authentication, it is necessary toexecute two types of authentication processing at high speed at almostthe same timings, and a plurality of cameras and a large number ofhardware resources are required.

The disclosure has been made in view of the above problems, and one ofobjects of the disclosure is to provide an authentication device or thelike that can execute authentication with high accuracy on anauthentication target who is moving with less hardware resources andwithin a predetermined time period.

Solution to Problem

In view of the above problems, an authentication device which is a firstaspect of the disclosure includes:

detection means for detecting an authentication target who is moving ina predetermined direction in a video of a predetermined area;

first image input means for inputting a first image in which an entirebody of the detected target is imaged;

first storage means for storing characteristic information of entirebodies of one or more targets to be authenticated;

first authentication means for calculating characteristic informationfrom the image of the entire body of the target imaged in the firstimage, comparing the calculated characteristic information with thecharacteristic information of the entire body stored in the firststorage means, and extracting candidate information of the one or moretargets from the first storage means based on a comparison result;

second image input means for inputting a second image in which an irisof at least one of a right eye and a left eye of the target who isdetected by the detection means and is moving in the predetermineddirection is imaged;

second storage means for storing characteristic information of irises ofthe right eyes and the left eyes of the one or more targets to beauthenticated; and

second authentication means for calculating a verification score bycomparing the characteristic information of the iris calculated from thesecond image with the characteristic information of the one or moreirises stored in the second storage means for each target included inthe candidate information, authenticating the target imaged in thesecond image based on the calculated verification score, and outputtingan authentication result.

An authentication method that is a second aspect of the disclosureincludes:

detecting an authentication target who is moving in a predetermineddirection in a video of a predetermined area;

inputting a first image in which an entire body of the detected targetis imaged;

calculating characteristic information from the image of the entire bodyof the target imaged in the first image, comparing the calculatedcharacteristic information with characteristic information of the entirebody stored in first storage means that stores characteristicinformation of entire bodies of one or more targets to be authenticatedto execute first authentication, and extracting candidate information ofthe one or more targets from the first storage means based on a resultof the first authentication;

inputting a second image in which an iris of at least one of a right eyeand a left eye of the target who is detected and is moving in thepredetermined direction is imaged; and

comparing characteristic information of one or more irises stored insecond storage means that stores characteristic information of theirises of the right eyes and the left eyes of the one or more targets tobe authenticated with characteristic information of the iris calculatedfrom the second image for each target included in the candidateinformation to calculate a verification score, executing secondauthentication on the target imaged in the second image based on thecalculated verification score, and outputting an authentication result.

An authentication program that is a third aspect of the disclosure andcauses a computer to achieve processing including:

detecting an authentication target who is moving in a predetermineddirection in a video of a predetermined area;

inputting a first image in which an entire body of the detected targetis imaged;

calculating characteristic information from the image of the entire bodyof the target imaged in the first image, comparing the calculatedcharacteristic information with characteristic information of the entirebody stored in first storage means that stores characteristicinformation of entire bodies of one or more targets to be authenticatedto execute first authentication, and extracting candidate information ofthe one or more targets from the first storage means based on a resultof the first authentication;

inputting a second image in which an iris of at least one of a right eyeand a left eye of the target who is detected and is moving in thepredetermined direction is imaged; and

comparing characteristic information of one or more irises stored insecond storage means that stores characteristic information of theirises of the right eyes and the left eyes of the one or more targets tobe authenticated with characteristic information of the iris calculatedfrom the second image for each target included in the candidateinformation to calculate a verification score, executing secondauthentication on the target imaged in the second image based on thecalculated verification score, and outputting an authentication result.

The authentication program may be stored in a storage medium.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram of a configuration of a biometric authenticationdevice according to a first example embodiment of the disclosure.

FIG. 2 is a diagram of an image of a target user who moves in a specificdirection.

FIG. 3 is a diagram of a first image acquired from the image of thetarget user who moves in the specific direction.

FIG. 4 is a diagram of a second image acquired from the image of thetarget user who moves in the specific direction.

FIG. 5 is a flowchart illustrating an operation example of the biometricauthentication device according to the first example embodiment of thedisclosure.

FIG. 6 is a diagram of a configuration of a biometric authenticationdevice according to a second example embodiment of the disclosure.

FIG. 7 is a diagram illustrating an exemplary configuration of datastored in a second storage unit.

FIG. 8 is a flowchart illustrating an operation example of the biometricauthentication device according to the second example embodiment of thedisclosure.

FIG. 9 is a diagram illustrating an exemplary configuration of abiometric authentication device according to a third example embodimentof the disclosure.

FIG. 10 is a flowchart illustrating an operation example of thebiometric authentication device according to the third exampleembodiment of the disclosure.

FIG. 11 is a diagram of a configuration of an information processingdevice that can be used in the first to the third example embodiments.

EXAMPLE EMBODIMENT

Hereinafter, each example embodiment will be described in detail withreference to the drawings. In the following description of the drawings,the same or similar part are denoted with the same or similar referencenumerals. However, the drawings schematically illustrate theconfigurations according to the example embodiments. Moreover, theexample embodiments described below are merely examples, and can beappropriately modified to the extent that they are essentially the same.

Authentication in each example embodiment is mainly biometricauthentication. An authentication target is mainly a living bodyincluding humans (user), animals, or the like. The authentication targetmay include, for example, a mannequin, other than a living body. Wheniris authentication is performed, right and left eyes of the target(including artificial eyes for impersonation) are authenticated. In thedescription of each example embodiment below, the target of theauthentication is also referred to as a “target user”.

Information used for biometric authentication includes a plurality oftypes of information such as an ultrasound graph, an image of a livingbody, or audio data. In the following description, for example, an image(specifically, iris image) will be mainly described. However, this doesnot intend to limit each example embodiment.

First Example Embodiment

To execute multi-modal authentication in a non-contact manner with auser who is an authentication target, it is preferable to use gaitauthentication, human shape authentication, face authentication, irisauthentication, or the like. The human shape authentication indicatesauthentication executed on the basis of features of the body of theauthentication target (for example, height, width of body, limb length,contour of face, or the like, or combination of these). The gaitauthentication indicates authentication executed on the basis offeatures of a walking pattern of the authentication target (for example,posture at the time of walking, stride length, arm swing, habitualmovement left-right asymmetry (whether to hole shoulder bag on the sameside or the like), or the like or combination of these). Among these,with the gait authentication and the human shape authentication, it iseasy to execute authentication from an image of an entire body of anauthentication target user who can be imaged from a distance. With theiris authentication, an authentication result with the highest accuracycan be expected if left and right eyes can be accurately imaged near theauthentication target user. In a case of walkthrough authentication, thetarget user moves from an entrance to an exit of an authentication gatein several seconds to several tens of seconds, although the time perioddepends on individuals. Therefore, the gait authentication or the humanshape authentication using the entire body image is executed on thetarget user near the entrance of the remote authentication gate as firstauthentication, and in addition, iris authentication using images of theleft and right eyes is executed on the target user who has moved to thevicinity of the exit of the authentication gate on the basis of a resultof the first authentication. Because candidates of the target user arenarrowed by the first authentication, the number of target usercandidates on which the iris authentication is executed is considerablysmall. As a result, an authentication result with high accuracy can bequickly obtained. Hereinafter, a biometric authentication device forexecuting the walkthrough authentication as described above will bedescribed in detail.

Biometric Authentication Device

As illustrated in FIG. 1, a biometric authentication device 100 includesa detection unit 11, a first image input unit 12, a second image inputunit 13, a first authentication unit 14, a first storage unit 15, asecond authentication unit 16, and a second storage unit 17.

The detection unit 11 detects a target user to be authenticated who ismoving in a predetermined direction in a video of a predetermined areafrom an entrance gate to an exit gate in an authentication executionarea.

The detection unit 11 is connected to an external camera 10 asillustrated in FIG. 1. The camera 10 is a camera that images a user tobe authenticated. There may be one or a plurality of cameras 10. Thedetection unit 11 detects a user who moves in a specific direction in animage imaged by the camera 10 (including moving image, still image. Thesame applies below). The movement in the specific direction means that auser walks from the entrance gate to the exit gate of the authenticationexecution area, for example, in a case of the walkthroughauthentication. The specific direction means a direction from theentrance gate to the exit gate. In a case of the authenticationexecution area illustrated in FIG. 2, the camera 10 first images theuser at a position 1 near the entrance gate. In the authenticationexecution area in FIG. 2, the entrance gate is arranged on the innerside, and the exit gate is arranged on the front side. The camera 10 isfixed at a position (wall, gate, or the like) where an image asillustrated in FIG. 2 can be captured.

When there is a user who moves from the position 1 to a position 2advanced by a predetermined distance in the specific direction (refer toFIG. 3) in the image of the user imaged by the camera 10, the detectionunit 11 determines that the above user is a target user to beauthenticated, and detects the user as the target user. Image data of aregion including an entire body of the detected target user is input tothe first image input unit 12 as a first image (refer to FIG. 3).Moreover, when there is a user who moves from the position 2 to aposition 3 advanced by a predetermined distance in the specificdirection (refer to FIG. 4) in the image of the user imaged by thecamera 10, the detection unit 11 determines that the above user is atarget user to be authenticated again, and detects the user as thetarget user. Image data of a region including left and right eyes of thedetected target user is input to the second image input unit 13 as asecond image (refer to FIG. 4).

Processing for selecting image regions including the body of the user(region including entire body of target user and region including leftand right eyes) may be transferred to the first image input unit 12 orthe second image input unit 13 after being executed by the detectionunit 11 or may be executed by the first image input unit 12 or thesecond image input unit 13 that has received the image captured by thecamera 10. Note that the above processing may be executed by the camera10.

When detecting the movement of the target user in a direction other thanthe predetermined direction, the detection unit 11 may stop an output ofan image to the first image input unit 12 and the second image inputunit 13. That is, the first image input unit 12 and the second imageinput unit 13 stop an input of the image of the target user who startsto move in the direction other than the predetermined direction. This isbecause, even if the user is wrongly determined as a target user once,there is a case where authentication is stopped in the middle becausethe user is an observer or a maintenance person in the authenticationexecution area or because the target user has left something, or thelike.

The first image input unit 12 receives the input of the first image(refer to FIG. 3) obtained by imaging the region including the entirebody of the user who moves in the specific direction from the detectionunit 11.

The first storage unit 15 stores characteristic information regardingentire bodies of one or more users to be authenticated. Here, thecharacteristic information regarding the entire body is characteristicinformation regarding a human shape used for human shape authentication,characteristic information regarding a gait used for gaitauthentication, or the like. The characteristic information regardingthe human shape is, for example, a pattern such as a height, a width ofa body, or the like extracted from a silhouette of an entire body image.The silhouette of the entire body image is extracted, for example, usinga background difference between an image of a color camera and an imageof an infrared camera. The characteristic information regarding the gaitis, for example, Spatio-Temporal Histograms of Oriented Gradient (STHOG)characteristic information that is a gait feature based on a time-spaceluminance gradient, frequency region characteristic information using aGait Silhouette Volume, or the like. As described above, in the firstauthentication, it is difficult to know a degree of light at a distance,and in addition, it is difficult to control light. Therefore, it isdesirable to surely and easily extract the characteristic information byusing the silhouette of the target user.

The first authentication unit 14 calculates the characteristicinformation from the image of the entire body of the target user imagedin the first image, compares the calculated characteristic informationwith characteristic information of the entire body stored in the firststorage unit 15, and extracts candidate information of one or moretarget users from the first storage unit 15 on the basis of a comparisonresult. The candidate information is information that can specify acandidate of the target user and is, for example, an IDentifier (ID) ofthe target user. The first authentication has a function as a prefilterof second authentication.

The first authentication unit 14 outputs the extracted candidateinformation of the target user to the second authentication unit 16.

The second image input unit 13 inputs the second image (refer to FIG. 4)obtained by imaging an iris of at least one of the right eye and theleft eye of the target user who is moving in the predetermined directionand is detected by the detection unit 11. Which one of the left eye andthe right eye the imaged eye is can be determined according to a shapeof an inner corner of each eye or the like. It is preferable that thesecond image input unit 13 input images of both eyes. However, in a casewhere the camera 10 cannot acquire the image of one eye (for example, itis not possible to perform imaging because bangs cover eye, it is notpossible to perform imaging due to reflection of glasses, or the like),an image of another eye that can be imaged is imaged.

The second storage unit 17 stores characteristic information of irisesof the right and the left eyes of one or more users to be authenticated.Note that the characteristic information of the iris is, for example, aniris code (refer to characteristic information in FIG. 7) generated onthe basis of the Daugman algorithm.

The second authentication unit 16 receives the input of the candidateinformation from the first authentication unit 14. The secondauthentication unit 16 compares the characteristic information of theiris calculated from the second image and the characteristic informationof one or more irises stored in the second storage unit 17 andcalculates a verification score for each target user included in thecandidate information, authenticates the target user imaged in the firstimage and the second image on the basis of the calculated verificationscore, and outputs an authentication result. The verification score is avalue of a result obtained by calculating the number of bits differentbetween an iris code of the target user and an iris code registered inthe second storage unit 17 (calculate hamming distance).

The second authentication unit 16 calculates the characteristicinformation of the iris from the second image associated with left/rightinformation for each target user included in the candidate information.The second image associated with the left/right information indicates aniris image of the right eye tagged as “right eye” and an iris image ofthe left eye tagged as “left eye” (refer to second image in FIG. 4).Note that either one of the left and the right eyes may be a tagged iriscode. A case where the iris code is used as the characteristicinformation of the iris will be described as an example. The secondauthentication unit 16 specifies a boundary line of an iris from animage of an iris received from the second image input unit 13 andextracts an iris portion. Moreover, the second authentication unit 16encodes an iris pattern by applying a two-dimensional Gabor filter toinformation regarding the extracted iris portion and generates an iriscode. The iris code is, for example, a 2048-bit digital encoding code.

The second authentication unit 16 compares the calculated characteristicinformation with characteristic information of a plurality of usersassociated with the left/right information stored in the second storageunit 17. Specifically, the second authentication unit 16 compares thecharacteristic information with characteristic information of only theright eye stored in the second storage unit 17 in a case of an irisimage tagged with the right eye, and compares the characteristicinformation with characteristic information of only the left eye storedin the second storage unit 17 in a case of an iris image tagged with theleft eye. The second authentication unit 16 obtains a verification scoreas a result of comparison. For example, when the calculated verificationscore is equal to or more than a predetermined threshold, the secondauthentication unit 16 authenticates that the user imaged in the secondimage is a registered user (valid user), and when the verification scoreis less than the predetermined threshold, the second authentication unit16 authenticates that the user imaged in the second image is not theregistered user. The second authentication unit 16 outputs anauthentication result to an external display unit 20. The display unit20 is a liquid crystal display or the like, and can display theauthentication result to be browsable by the target user or anadministrator of the authentication execution area. Note that the userimaged in the second image is the user imaged in the first image. Inaddition, the authentication result may be notified with voicenotifications by a speaker or a buzzer, lighting of lamps, or the like.

Operation of Biometric Authentication Device

An operation of the biometric authentication device 100 according to thefirst example embodiment will be described with reference to theflowchart in FIG. 5. Note that it is assumed that the first storage unit15 store in advance the characteristic information of the entire body ofthe plurality of users who may be an authentication target. It isassumed that the second storage unit 17 store in advance characteristicinformation of irises of the right eyes and the left eyes of theplurality of users who may be an authentication target.

In step S101, the detection unit 11 detects a user in a video of theauthentication execution area imaged by the camera 10 (refer to FIG. 2).

In step S102, the detection unit 11 detects whether the user is movingin the direction from the entrance to the exit of the authenticationgate (refer to FIG. 3). As a result of the detection, if the user ismoving in the direction from the entrance to the exit, the detectionunit 11 sets this user as an authentication target user, acquires animage of an entire body of the target user from the camera 10, andoutputs the image to the first image input unit 12. As a result of thedetection, if the user is not moving in the direction from the entranceto the exit, the procedure returns to step S101.

In step S103, the first image obtained by imaging the entire body of thetarget user is input to the first image input unit 12.

In step S104, the first authentication unit 14 calculates thecharacteristic information from the image of the entire body of thetarget user imaged in the first image, compares the calculatedcharacteristic information with the characteristic information of theentire body stored in the first storage unit 15, and extracts candidateinformation of one or more target users from the first storage unit 15on the basis of a comparison result.

In step S105, the first authentication unit 14 temporarily holds theextracted candidate information of the target user.

In step S106, the detection unit 11 detects whether the target user iscontinuously moving in the direction from the entrance to the exit ofthe authentication gate (refer to FIG. 4). As a result of the detection,if the target user is moving in the direction from the entrance to theexit, the detection unit 11 acquires an image of a region of left andright eyes of the target user from the camera 10, and outputs the imageto the second image input unit 13. As a result of the detection, if thetarget user is not moving in the direction from the entrance to theexit, the detection unit 11 instructs the first authentication unit 14to discard the holding candidate information of the target user (stepS120). The first authentication unit 14 discards the candidateinformation according to this instruction, and the procedure returns tostep S101.

In step S107, the second image obtained by imaging an iris of at leastone of the right eye and the left eye of the target user imaged by thecamera 10 is input to the second image input unit 13.

In step S108, the second authentication unit 16 receives the candidateinformation from the first authentication unit 14, compares thecharacteristic information of the iris calculated from the second imagewith the characteristic information of one or more irises stored in thesecond storage unit 17 for each target user included in the candidateinformation, and calculates a verification score. The secondauthentication unit 16 authenticates the target user imaged in the firstimage and the second image on the basis of the calculated verificationscore and outputs the authentication result to the display unit 20.

In step S109, the display unit 20 displays the input authenticationresult. The display unit 20 displays the input authentication result.

With that, the operation of the biometric authentication device 100 isterminated.

Effects of First Example Embodiment

According to the first example embodiment, it is possible to executehighly accurate biometric authentication on an authentication targetuser who is moving with less hardware resources and within apredetermined time period. This is because the first authentication unit14 narrows candidates of the target user on the basis of the image ofthe entire body of the target user, and the second authentication unit16 determines whether the target user is a registered user (valid user)from among the candidates of the target user on the basis of the imageof the iris of the target user. First, gait authentication or humanshape authentication is executed on the target user near the entrance ofthe authentication gate at a remote place as the first authentication.Next, according to the result of the first authentication, irisauthentication is executed on the target user who has moved near theexit of the authentication gate in the vicinity. Because candidates ofthe target user are narrowed by the first authentication, the number oftarget user candidates on which the iris authentication is executed isconsiderably small. As a result, an authentication result with highaccuracy can be quickly obtained. Because the first authentication andthe second authentication are separately executed with a timedifference, two types of authentication can be executed without using alarge number of hardware resources. The detection unit 11 detects only auser who moves in the predetermined direction in the authenticationexecution area, and excludes the user from the detection target in acase where the user stops moving in the predetermined direction.Therefore, the first authentication unit 14 and the secondauthentication unit 16 can execute authentication processing only on thetarget user. This can contribute to the quick authentication with highaccuracy that does not need a large number of hardware resources.

Second Example Embodiment

As features of the iris, colors and shapes of left and right irises ofthe same person are different from each other. Therefore, the featuresof the left and the right irises are also different from each other.Therefore, even in a case of the same person, there is an eye that canbe easily identified or an eye that is difficult to be identified. Theeye that can be easily identified needs a short time for theauthentication processing and is identified with higher accuracy.Therefore, it is possible to execute authentication with higher accuracyin a shorter time when the authentication processing is executed usingthe left or right eye that can be more easily identified. In the secondexample embodiment, a biometric authentication device or the like thatexecutes the authentication processing while weighting the eye that canbe easily identified will be described.

Biometric Authentication Device

As illustrated in FIG. 6, a biometric authentication device 200 includesa detection unit 11, a first image input unit 12, a second image inputunit 13, a first authentication unit 14, a first storage unit 15, asecond authentication unit 16 a, a second storage unit 17 a, adetermination unit 21, and an adjustment unit 22. Note that thedetection unit 11 is connected to an external camera 10. The secondauthentication unit 16 a is connected to an external display unit 20.

The second storage unit 17 a stores characteristic information and areliability score of a right eye of each user and characteristicinformation and a reliability score of a left eye for each identifiableID that is associated with a user to be authenticated (refer to FIG. 7).The reliability is a value that indicates how easy the target user andother user are identified, and the reliability score indicates thereliability as a value of zero to 100%. An example of a method forcalculating the reliability score will be described. Each ID of theregistered user stored in the second storage unit 17 a is set to i(i={1, 2, 3, . . . , N}; N, N indicates total number of registeredusers), characteristic information (characteristic vector) of an irisimage of a right eye of each registered user is set to X_(right) (i),characteristic information (characteristic vector) of an iris image of aright eye of a current target user (person to be collated) is set toY_(right), and a correlation (for example, normalized cross-correlation)between X_(right) (i) and Y_(right) is calculated for all the registeredusers i. After the calculation, a ratio (=largest correlationvalue/second correlation value) between the largest correlation value(that is, correlation value between identical persons (a case wheretarget user matches registered user)) and a second correlation value(correlation value between person and registered user who is otherperson having highest correlation value), and the calculated value isset as a reliability S_(right). Similarly, similar processing isexecuted on the left eye, and the calculated value is set as areliability S_(left). These reliabilities S_(right) and S_(left) arenormalized and are converted into values of zero % to 100% in such a wayas to obtain reliability scores (for example, left eye 20%, right eye80%). Although there are various methods for normalizing thereliability, for example, when the reliability score is calculated as(%)=100×(S−1)/(M−1) (at this time, 1≤S≤M; S indicates either one ofS_(right) or S_(left), M indicates maximum value of reliability. Maximumvalue is set by designer or the like in advance, and reliability in acase of M<S is set as 100). The method for calculating the reliabilityscore is not limited to the above. As the value of the reliability scoreincreases, the characteristic information of the target user can be moreeasily identified than the characteristic information of the other user(rare iris code). For example, in a case of a user ID “1” illustrated inFIG. 7, because a reliability score of the right eye is 80% and areliability score of the left eye is 20%, an iris of the right eye ofthis user is characteristic, and this indicates that there arerelatively less users who have similar characteristic information. Onthe other hand, an iris of the left eye of the user is not verycharacteristic, and this indicates that there are a large number ofusers who have similar characteristic information. In such a case,because to use the right eye is efficient for the authenticationprocessing, even in a case where second images of both eyes can beimaged, it can be said that it is desirable to execute theauthentication processing using the second image of the right eye. Onthe other hand, in a case where only the second image of the left eyecan be imaged for some reason, even if a verification score of theauthentication is low, it is possible to estimate that the lowverification score is caused by the low reliability score of the lefteye. In this case, the biometric authentication device 200 can requestthe user to image an iris image again. Specifically, the biometricauthentication device 200 requests the user to move from the entrancegate to the exit gate again for authentication via the display unit 20or the like. In a case where the eye having the higher score is hiddenby hairs or the like, the second authentication unit 16 a may present adocument or the like, on the display unit 20, that requests the user tocooperate to clearly image the eye having the higher reliability scorewith the camera 10.

In addition to the operation of the second authentication unit 16 inFIG. 1, the second authentication unit 16 a executes authenticationusing a value obtained by adding the reliability score to theverification score. The second authentication unit 16 a calculates averification score obtained by comparing characteristic information ofan iris calculated from a second image associated with left/rightinformation with one or more pieces of characteristic information storedin the second storage unit 17 a related to the left/right information.Moreover, the second authentication unit 16 a specifies a target user onthe basis of the verification score, acquires a reliability scorerelated to the target user from the second storage unit 17 a, andcalculates a score in which the reliability score is reflected on thecalculated verification score. For example, if the user has the ID of“1” in FIG. 7, a reliability score of the right eye is 80%, and areliability score of the left eye is 20%. Therefore, in a case where theverification scores of the second images of both eyes are calculated,the second authentication unit 16 a weights the verification score ofthe right eye with the reliability score of the right eye and weightsthe verification score of the left eye with the reliability score of theleft eye. At this time, the second authentication unit 16 a may increasea priority of the eye having a higher reliability and may weight onlythe verification score of the right eye with the reliability score ofthe right eye. As a result, a score with a higher reliability can beobtained. The weighting indicates, for example, to obtain a calculationresult by multiplying or adding both scores or substituting both scoresinto a predetermined formula. The second authentication unit 16 aexecutes the authentication processing using the weighted score.

The determination unit 21 determines which one of images of the left eyeor the right eye of the user the second image is on the basis ofinformation including the first image and outputs left/right informationindicating a determination result in association with the second image.As will be described later, the determination unit 21 outputs an imageof an iris portion as illustrated in FIG. 4. In the example embodiment,for the determination regarding the left and the right eyes, as anexample, one of the two following methods is used. As a first method,the determination unit 21 executes matching processing by applying apredetermined template, used to detect a positional relationship betweena contour, both eyes, or the like of the face, to a face region of theuser in the first image and determines which one of the left eye or theright eye of the user the second image is. To detect the positionalrelationship between the both eyes, the face of the user needs to facethe front side of the camera 10. However, by setting the camera 10 at aposition where the camera 10 can image a user who is moving toward apredetermined traveling direction, a user who faces the camera 10 isinevitably set as a determination target. As a second method, thedetermination unit 21 compares pixels in regions of the right eye andthe left eye of the user in the first image with pixels in regions ofthe right eye and the left eye of the user in the second image anddetermines whether the second image is relevant to the left eye or theright eye of the user. In this case, the determination unit 21 extractsthe pixels in the each regions of the right eye and the left eye of theuser in the first image that is an image of an entire body, compares theextracted pixels with the pixels of the regions of eyes imaged in thesecond image, and determines which one of the left eye or the right eyethe eye imaged in the second image is, according to a similarity withthe compared pixel. For the comparison of the pixels, a contour tracingalgorithm using a chain code, a principal component analysis method, athree-dimensional phase limited correlation method, or the like may beused. The method for determining the left and the right eyes is notlimited to the above.

The first image and the second image may be imaged by the single camera10. However, in this case, it is preferable that the camera 10 canquickly switch a magnification of a telescopic function used to image afirst image and a second image of a subject.

The adjustment unit 22 adjusts an imaging time. The adjustment unit 22performs adjustment in such a way that the second authentication unit 16executes second authentication after first authentication by the firstauthentication unit 14 and the first authentication and the secondauthentication are completed within a time period in which the detectionunit 11 can detect a target user who is moving in a predetermineddirection in a video of an authentication execution area. That is,although each target user passes through from an entrance of anauthentication gate to an exit in several seconds to several tens ofseconds individually, if the first authentication and the secondauthentication are not completed within this time period, the targetuser cannot terminate the authentication and exit from the exit. Inconsideration of a moving speed of the target user, the adjustment unit22 adjusts a timing of the first authentication by the firstauthentication unit 14 and a timing of the second authentication by thesecond authentication unit 16 a and smoothly completes theauthentication processing before the target user exits from the exit ofthe authentication gate.

Operations of the other units are similar to those of the first exampleembodiment.

Operation of Biometric Authentication Device

An operation of the biometric authentication device 200 according to thesecond example embodiment will be described with reference to theflowchart in FIG. 8. Note that it is assumed that the first storage unit15 store in advance the characteristic information of the entire body ofthe plurality of users who may be an authentication target. It isassumed that the second storage unit 17 a stores characteristicinformation of irises of the right eye and the left eye of the pluralityof users who may be an authentication target and a reliability score(refer to FIG. 7) in advance.

Steps S201 to S207 and S220 are similar to steps S101 to S107 and S120in FIG. 5.

In step S208, the determination unit 21 determines which one of the lefteye or the right eye of the target user the second image is on the basisof the information including the first image and outputs a determinationresult to the second authentication unit 16 a in association with thesecond image as the left/right information.

In step S209, the second authentication unit 16 a receives candidateinformation of the target user from the first authentication unit 14.Moreover, the second authentication unit 16 a receives the second imageassociated with the left/right information from the determination unit21. The second authentication unit 16 a compares characteristicinformation of the iris calculated from the received second image withcharacteristic information of the target user included in the candidateinformation stored in the second storage unit 17 related to theleft/right information and calculates a verification score. The secondauthentication unit 16 a specifies a target user on the basis of thecalculated verification score, acquires a reliability score related tothe target user from the second storage unit 17 a, and weights thecalculated verification score with the reliability score (hereinafter,described as weighted verification score). At this time, the secondauthentication unit 16 a may prioritize an eye having a higherreliability and weight a verification score of the eye having the higherpriority with a reliability score of the eye. The second authenticationunit 16 a authenticates the target user imaged in the first image andthe second image on the basis of the weighted score. Specifically, thesecond authentication unit 16 a authenticates that the user imaged inthe first image and the second image is a registered user (valid user)if the weighted verification score is equal to or more than apredetermined threshold and authenticates that the user imaged in thefirst image and the second image is not the registered user if theweighted verification score is equal to or less than a predeterminedthreshold.

In step S210, the second authentication unit 16 a outputs anauthentication result to the external display unit 20. The display unit20 displays the input authentication result.

With that, the operation of the biometric authentication device 200 isterminated.

Effect of Second Example Embodiment

According to the second example embodiment, it is possible to executethe authentication processing with higher accuracy, in addition to theeffect of the first example embodiment. This is because the secondauthentication unit 16 a specifies the target user from the secondstorage unit 17 a on the basis of the calculated verification score,acquires the reliability score related to the target user from thesecond storage unit 17 a, and weights the calculated verification scorewith the reliability score. Moreover, this is because the secondauthentication unit 16 a prioritizes the eye having the higherreliability and weights the verification score of the eye having thehigher priority with the reliability score of the eye.

Third Example Embodiment

In the first and the second example embodiments, only the entire bodyauthentication (human shape authentication or gait authentication) andthe iris authentication are executed. However, multi-modalauthentication combined with third authentication different from thefirst authentication and the second authentication may be executed. Forexample, in the first and the second example embodiments, because theentire body image and the left and the right eye images of the movinguser are used, it is preferable to execute face authentication betweenthe first authentication (entire body) and the second authentication(eye) from the viewpoint of a timing of authentication target detection.In the third example embodiment, a biometric authentication device orthe like in which three types of biometric authentication are combinedwill be described.

Biometric Authentication Device

As illustrated in FIG. 9, a biometric authentication device 300 includesa detection unit 11, a first image input unit 12, a second image inputunit 13, a first authentication unit 14, a first storage unit 15, asecond authentication unit 16 b, a second storage unit 17 a, adetermination unit 21, an adjustment unit 22 a, a third image input unit31, a third storage unit 32, and a third authentication unit 33. Thedetection unit 11 is connected to an external camera 10. The secondauthentication unit 16 b is connected to an external display unit 20.

The third image input unit 31 inputs a third image in which a faceregion of a target user who is moving in a predetermined direction andis detected by the detection unit 11 is imaged between an input of animage by the first image input unit 12 and an input of an image by thesecond image input unit 13.

The third storage unit 32 stores characteristic information of faces ofone or more users to be authenticated. The characteristic information ofthe face is, for example, feature points indicating characteristicshapes, a positional relationship, or the like of eyes, a nose, an amouth end in the face extracted as a face feature amount.

The third authentication unit 33 compares characteristic information ofthe face calculated from the third image with the characteristicinformation of one or more faces stored in the third storage unit foreach target user included in candidate information output in firstauthentication, calculates a second verification score and extractscandidate information of one or more target users from the third storageunit on the basis of the calculated second verification score. The thirdauthentication unit 33 outputs the extracted candidate information tothe second authentication unit 16 b.

Although the second authentication unit 16 b has a function similar tothe second authentication unit 16 (refer to FIG. 1) and the secondauthentication unit 16 a (refer to FIG. 6) described above, the secondauthentication unit 16 b executes iris authentication of the target useron the basis of the candidate information input from the thirdauthentication unit 33.

The adjustment unit 22 a adjusts an authentication timing in such a waythat the third authentication is executed after the firstauthentication, the second authentication is executed after the thirdauthentication, and the first authentication, the third authentication,and the second authentication are completed within a time period inwhich a target user who is moving in a predetermined direction in avideo of an authentication execution area can be detected.

Operations of other units are similar to those in the first and secondexample embodiments.

Operation of Biometric Authentication Device

An operation of the biometric authentication device 300 according to thethird example embodiment will be described with reference to theflowchart in FIG. 10. Note that it is assumed that the first storageunit 15 store in advance the characteristic information of the entirebody of the plurality of users who may be an authentication target. Itis assumed that the second storage unit 17 a stores in advancecharacteristic information of irises of the right eye and the left eyeof the plurality of users who may be an authentication target. Thecharacteristic information of the iris may store information to which areliability score is added (refer to FIG. 7). It is assumed that thethird storage unit 32 store characteristic information of the faces ofthe plurality of users to be authenticated in advance.

Steps S301 to S305 and S320 are similar to steps S201 to S205 and S220in FIG. 8.

In step S306, the detection unit 11 detects whether a user is moving ina direction from an entrance to an exit of an authentication gate. As aresult of the detection, if the user is moving in the direction from theentrance to the exit, the detection unit 11 acquires an image of a faceof the target user from the camera 10 and outputs the image to the thirdimage input unit 31. As a result of the detection, if the user is notmoving in the direction from the entrance to the exit, the procedureproceeds to step S320, and returns to step S301 after the image and thecandidate information that are temporarily held by the firstauthentication unit 14 are deleted.

In step S307, the third image input unit 31 inputs a third image inwhich the face of the target user is imaged. At this time, the thirdimage input unit 31 may select a face region from the image of thetarget user and input the selected region as the third image.

In step S308, the third authentication unit 33 calculates characteristicinformation from the image of the face region of the target user imagedin the third image, compares the calculated characteristic informationwith the characteristic information of the face stored in the thirdstorage unit 32, and extracts candidate information of one or moretarget users from the third storage unit 32 on the basis of a comparisonresult.

In step S309, the third authentication unit 33 temporarily holds theextracted candidate information of the target user.

Steps S310 to S314 are similar to steps S206 to S210 in FIG. 8.

With that, the operation of the biometric authentication device 300 isterminated.

Effect of Third Example Embodiment

According to the third example embodiment, it is possible to provide thebiometric authentication device 300 that has higher authenticationaccuracy than the biometric authentication devices described in thefirst and second example embodiments, in addition to the effects of thefirst and second example embodiments. This is because the faceauthentication is combined as the third authentication between the firstauthentication (entire body) and the second authentication (eye).Moreover, this is because, the gait authentication or the like (entirebody), the face authentication (face), the iris authentication (left andright eyes), and after arrangements of authentication position that mosteasily images the target user according to the movement of the targetuser are combined from the entrance to the exit of the authenticationexecution area, the adjustment unit 22 a adjusts the authenticationtiming in such a way that the first authentication to the thirdauthentication are completed, in order of the first authentication, thethird authentication, and the second authentication, within a timeperiod in which the target user who is moving in the predetermineddirection in the video of the authentication execution area can bedetected.

The example embodiments may be used in combination.

Information Processing Device

In each example embodiment described above, some or all of thecomponents of the biometric authentication devices illustrated in FIGS.1, 6, 9, or the like can be achieved, for example, by using anycombination of an information processing device 500 and a program asillustrated in FIG. 11. The information processing device 500 includes,for example, the following configurations.

-   Central Processing Unit (CPU) 501-   Read Only Memory (ROM) 502-   Random Access Memory (RAM) 503-   Storage device 505 that stores program 504 and other pieces of data-   Drive device 507 that reads/writes from/to recording medium 506-   Communication interface 508 that connects to communication network    509-   Input/output interface 510 that inputs/outputs data-   Bus 511 that connects components

Each component of the biometric authentication device in each exampleembodiment of the application is achieved by the CPU 501 acquiring andexecuting the program 504 that enables the functions of theseconstituent elements. The program 504 that achieves the function of eachcomponent of the biometric authentication device is stored, for example,in the storage device 505 and the RAM 503 in advance and is read by theCPU 501 as needed. The program 504 may be supplied to the CPU 501 viathe communication network 509, or the program 504 may be stored in therecording medium 506 in advance and the drive device 507 may read theprogram and supply the read program to the CPU 501.

There are various modifications of the method for achieving each device.For example, the biometric authentication device may be achieved by anycombination of an individual information processing device and a programfor each component. The plurality of components included in thebiometric authentication device may be achieved by any combination of asingle information processing device 500 and a program.

Some or all of the components of the biometric authentication device areachieved by other general or dedicated circuits, processors, or thelike, and a combination thereof. These may be configured by a singlechip or a plurality of chips connected via a bus.

Some or all of the components of the biometric authentication device maybe achieved by a combination of the circuit or the like and the programdescribed above.

In a case where some or all of the components of the biometricauthentication device are achieved by a plurality of informationprocessing devices, circuits, or the like, the plurality of informationprocessing devices, circuits, or the like may be centrally ordispersedly arranged. For example, the information processing device,the circuit, or the like may be achieved as a form in which each one isconnected via a communication network, such as a client server system, acloud computing system, or the like.

The whole or part of the example embodiments disclosed above can bedescribed as, but not limited to, the following supplementary notes.

Supplementary Note 1

An authentication device comprising:

detection means for detecting an authentication target who is moving ina predetermined direction in a video of a predetermined area;

first image input means for inputting a first image in which an entirebody of the detected target is imaged;

first storage means for storing characteristic information of entirebodies of one or more targets to be authenticated;

first authentication means for calculating characteristic informationfrom an image of the entire body of the target imaged in the firstimage, comparing the calculated characteristic information with thecharacteristic information of the entire body stored in the firststorage means, and extracting candidate information of the one or moretargets from the first storage means based on a comparison result;

second image input means for inputting a second image in which an irisof at least one of a right eye and a left eye of the target who isdetected by the detection means and is moving in the predetermineddirection is imaged;

second storage means for storing characteristic information of irises ofthe right eyes and the left eyes of the one or more targets to beauthenticated; and

second authentication means for comparing characteristic information ofthe iris calculated from the second image with the characteristicinformation of one or more irises stored in the second storage means,calculating a verification score for each target included in thecandidate information, authenticating the target imaged in the secondimage based on the calculated verification score, and outputting anauthentication result.

Supplementary Note 2

The authentication device according to supplementary note 1, in which

when the detection means detects a movement of the target in a directionother than the predetermined direction, the first image input means andthe second image input means stop input of an image of the target.

Supplementary Note 3

The authentication device according to supplementary note 1 or 2,further comprising:

determination means for determining whether the second image is of theleft eye or the right eye of the target based on information includingthe first image and outputting a determination result in associationwith the second image as left/right information, in which

the second authentication means compares characteristic information ofan iris calculated from the second image associated with the left/rightinformation with one or more pieces of characteristic information storedin the second storage means related to the left/right information andcalculates the verification score.

Supplementary Note 4

The authentication device according to supplementary note 1, in which

the second storage means stores the characteristic information of theirises of the right eyes and the left eyes of the one or more targets tobe authenticated and reliability scores of the right eyes and the lefteyes of the one or more targets to be authenticated, and

the second authentication means specifies the target based on theverification score, acquires the reliability score related to the targetfrom the second storage means, and calculates a weighted verificationscore obtained by weighting the reliability score to the verificationscore.

Supplementary Note 5

The authentication device according to any one of supplementary notes 1,3, and 4, in which

the second authentication means prioritizes an eye having a higher valueindicating the reliability score and calculates the weightedverification score.

Supplementary Note 6

The authentication device according to supplementary note 3, in which

the determination means applies a predetermined template to a faceregion of the target in the first image and determines whether the twoimages are relevant to the left eye or the right eye of the target.

Supplementary Note 7

The authentication device according to supplementary note 1, furthercomprising:

adjustment means for performing adjustment in such a way that the secondauthentication means executes second authentication after firstauthentication by the first authentication means and the firstauthentication and the second authentication are completed within a timeperiod in which the detection means is able to detect the target who ismoving in the predetermined direction in the video of the predeterminedarea.

Supplementary Note 8

The authentication device according to supplementary note 1, furthercomprising:

third image input means for inputting a third image in which a face ofthe target who is moving in the predetermined direction and is detectedby the detection means is imaged between input of an image by the firstimage input means and input of an image by the second image input means;

third storage means for storing characteristic information of faces ofthe one or more targets to be authenticated; and

third authentication means for comparing characteristic information ofthe face calculated from the third image with the characteristicinformation of the one or more faces stored in the third storage meansfor each target included in the candidate information output by thefirst authentication means and extracting candidate information of theone or more targets from the third storage means based on a comparisonresult.

Supplementary Note 9

The authentication device according to supplementary note 7, in which

the adjustment means performs adjustment in such a way that the thirdauthentication means executes third authentication after the firstauthentication by the first authentication means, the secondauthentication means executes the second authentication after the thirdauthentication, and the first authentication, the third authentication,and the second authentication are completed within a time period inwhich the detection means is able to detect the target who is moving inthe predetermined direction in the video of the predetermined area.

Supplementary Note 10

An authentication method comprising:

detecting an authentication target who is moving in a predetermineddirection in a video of a predetermined area;

inputting a first image in which an entire body of the detected targetis imaged;

calculating characteristic information from an image of the entire bodyof the target imaged in the first image, comparing the calculatedcharacteristic information with characteristic information of the entirebody stored in first storage means that stores characteristicinformation of entire bodies of one or more targets to be authenticatedto execute first authentication, and extracting candidate information ofthe one or more targets from the first storage means based on a resultof the first authentication;

inputting a second image in which an iris of at least one of a right eyeand a left eye of the target who is detected and is moving in thepredetermined direction is imaged; and

comparing characteristic information of one or more irises stored insecond storage means that stores characteristic information of irises ofthe right eyes and the left eyes of the one or more targets to beauthenticated with characteristic information of an iris calculated fromthe second image for each target included in the candidate information,calculating a verification score, executing second authentication on thetarget imaged in the second image based on the calculated verificationscore, and outputting an authentication result.

Supplementary Note 11

The authentication method according to supplementary note 10, in which

in the detection, when a movement of the target in a direction otherthan the predetermined direction is detected, inputs of a first imageand a second image of the target are stopped.

Supplementary Note 12

The authentication method according to supplementary note 10 or 11,further comprising:

determining whether the second image is of the left eye or the right eyeof the based on information including the first image and outputting adetermination result in association with the second image as left/rightinformation, in which

in the second authentication, characteristic information of an iriscalculated from the second image associated with the left/rightinformation is compared with one or more pieces of characteristicinformation stored in the second storage means related to the left/rightinformation, and the verification score is calculated.

Supplementary Note 13

The authentication method according to supplementary note 10, in which

the second storage means stores the characteristic information of theirises of the right eyes and the left eyes of the one or more targets tobe authenticated and reliability scores of the right eyes and the lefteyes of the one or more targets to be authenticated, and

in the second authentication, the target is specified based on theverification score, the reliability score related to the target isacquired from the second storage means, and a weighted verificationscore obtained by weighting the reliability score to the verificationscore is calculated.

Supplementary Note 14

The authentication method according to any one of supplementary notes10, 12, and 13, in which

in the second authentication, an eye having a higher value indicatingthe reliability score is prioritized, and the weighted verificationscore is calculated.

Supplementary Note 15

The authentication method according to supplementary note 12, in which

in the determination, a predetermined template is applied to a faceregion of the target in the first image, and it is determined whetherthe two images are relevant to the left eye or the right eye of thetarget.

Supplementary Note 16

The authentication method according to supplementary note 10, furthercomprising:

performing adjustment in such a way that the second authentication isexecuted after the first authentication, and the first authenticationand the second authentication are completed within a time period inwhich it is possible to perform the detection of the target who ismoving in the predetermined direction in the video of the predeterminedarea.

Supplementary Note 17

The authentication method according to supplementary note 10, furthercomprising:

inputting a third image in which a face of the detected target who ismoving in the predetermined direction is imaged between input of thefirst image and input of the second image; and

comparing characteristic information of the face calculated from thethird image with the characteristic information of the one or more facesstored in third storage means that stores characteristic information offaces of the one or more targets to be authenticated for each targetincluded in the candidate information output in the firstauthentication, calculating a second verification score, and extractingcandidate information of the one or more targets from the third storagemeans based on the calculated second verification score.

Supplementary Note 18

The authentication method according to supplementary note 16, in which

in the adjustment, adjustment is performed in such a way that the thirdauthentication is executed after the first authentication, the secondauthentication is executed after the third authentication, and the firstauthentication, the third authentication, and the second authenticationare completed within a time period in which it is possible to performthe detection of the target who is moving in the predetermined directionin the video of the predetermined area.

Supplementary Note 19

A storage medium that stores an authentication program for causing acomputer to achieve processing comprising:

detecting an authentication target who is moving in a predetermineddirection in a video of a predetermined area;

inputting a first image in which an entire body of the detected targetis imaged;

calculating characteristic information from an image of the entire bodyof the target imaged in the first image, comparing the calculatedcharacteristic information with characteristic information of the entirebody stored in first storage means that stores characteristicinformation of entire bodies of one or more targets to be authenticatedto execute first authentication, and extracting candidate information ofthe one or more targets from the first storage means based on a resultof the first authentication;

inputting a second image in which an iris of at least one of a right eyeand a left eye of the target who is detected and is moving in thepredetermined direction is imaged; and

comparing characteristic information of one or more irises stored insecond storage means that stores the characteristic information of theirises of the right eyes and the left eyes of the one or more targets tobe authenticated with characteristic information of an iris calculatedfrom the second image for each target included in the candidateinformation, calculating a verification score, executing secondauthentication on the target imaged in the second image based on thecalculated verification score, and outputting an authentication result.

Supplementary Note 20

The storage medium according to supplementary note 19, in which

in the detection, when a movement of the target in a direction otherthan the predetermined direction is detected, inputs of a first imageand a second image of the target are stopped.

Supplementary Note 21

The storage medium according to supplementary note 19 or 20, furthercomprising:

determining whether the second image is of the left eye or the right eyeof the target based on information including the first image andoutputting a determination result in association with the second imageas left/right information, in which

in the second authentication, characteristic information of an iriscalculated from the second image associated with the left/rightinformation is compared with one or more pieces of characteristicinformation stored in the second storage means related to the left/rightinformation, and the verification score is calculated.

Supplementary Note 22

The storage medium according to supplementary note 19, in which

the second storage means stores the characteristic information of theirises of the right eyes and the left eyes of the one or more targets tobe authenticated and reliability scores of the right eyes and the lefteyes of the one or more targets to be authenticated, and

in the second authentication, the target is specified based on theverification score, the reliability score related to the target isacquired from the second storage means, and a weighted verificationscore obtained by weighting the reliability score to the verificationscore is calculated.

Supplementary Note 23

The storage medium according to any one of supplementary notes 19, 21,and 22, in which

in the second authentication, an eye having a higher value indicatingthe reliability score is prioritized, and the weighted verificationscore is calculated.

Supplementary Note 24

The storage medium according to supplementary note 21, in which

in the determination, a predetermined template is applied to a faceregion of the target in the first image, and it is determined whetherthe two images are relevant to the left eye or the right eye of thetarget.

Supplementary Note 25

The storage medium according to supplementary note 19, furthercomprising:

performing adjustment in such a way that the second authentication isexecuted after the first authentication, and the first authenticationand the second authentication are completed within a time period inwhich it is possible to perform the detection of the target who ismoving in the predetermined direction in the video of the predeterminedarea.

Supplementary Note 26

The storage medium according to supplementary note 19, furthercomprising:

inputting a third image in which a face of the detected target who ismoving in the predetermined direction is imaged between input of thefirst image and input of the second image; and

comparing characteristic information of the face calculated from thethird image with characteristic information of one or more faces storedin third storage means that stores characteristic information of facesof the one or more targets to be authenticated for each target includedin the candidate information output in the first authentication,calculating a second verification score, and extracting candidateinformation of the one or more targets from the third storage meansbased on the calculated second verification score.

Supplementary Note 27

The storage medium according to supplementary note 25, in which

the adjustment is performed in such a way that the third authenticationis executed after the first authentication, the second authentication isexecuted after the third authentication, and the first authentication,the third authentication, and the second authentication are completedwithin a time period in which it is possible to perform the detection ofthe target who is moving in the predetermined direction in the video ofthe predetermined area.

While the application has been particularly shown and described withreference to exemplary embodiments thereof, the application is notlimited to these embodiments. It will be understood by those of ordinaryskill in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the exampleembodiments as defined by the claims.

REFERENCE SIGNS LIST

-   10 camera-   11 detection unit-   12 first image input unit-   13 second image input unit-   14 first authentication unit-   15 first storage unit-   16 second authentication unit-   16 a second authentication unit-   16 b second authentication unit-   17 second storage unit-   17 a second storage unit-   20 display unit-   21 determination unit-   22 adjustment unit-   22 a adjustment unit-   31 third image input unit-   32 third storage unit-   33 third authentication unit-   100 biometric authentication device-   200 biometric authentication device-   300 biometric authentication device-   500 information processing device-   501 CPU-   503 RAM-   504 program-   505 storage device-   506 recording medium-   507 drive device-   508 communication interface-   509 communication network-   510 input/output interface-   511 bus-   507 drive device-   508 communication interface-   509 communication network-   510 input/output interface-   511 bus

1. An authentication device comprising: a memory configured to storeinstructions; and at least one processor configured to execute theinstructions to: extract first biological information of anauthentication target from a first image, the authentication targetbeing moving in a predetermined direction in a video of a predeterminedarea, the first image being an image by capturing the authenticationtarget; extract, as candidate information of the authentication target,one or more sets of registrant information from a storage by performinga first authentication using the first biological information, thestorage storing a plurality of sets of registrant information about aplurality of registrants to be authenticated; hold the extractedcandidate information temporarily; extract second biological informationof the authentication target from a second image, the second biologicalinformation being different type from the first biological information,the second image being an image by capturing the authentication targetmoving in the predetermined direction after the first image is captured;determine, as a second authentication, whether to authenticate theauthentication target by comparing the second biological information andone or more sets of biological information of being included in one ormore sets of candidate information and the same type as the secondbiological information, the second authentication being anauthentication process with higher accuracy than the firstauthentication; and discard the held candidate information when theauthentication target does not move in the predetermined directionbetween time the first image is captured and time the second image iscaptured.
 2. The authentication device according to claim 1, wherein thesecond authentication is iris authentication.
 3. The authenticationdevice according to claim 2, wherein the at least one processor isfurther configured to execute the instructions to: in the secondauthentication, calculate a verification score with respect to theauthentication target by comparing characteristic information calculatedfrom an iris of an eye of the authentication target in the second imagewith one or more sets of characteristic information about irises of eyesincluded in one or more sets of candidate information; authenticate theauthentication target using the calculated verification score; andoutput a authentication result.
 4. The authentication device accordingto claim 3, wherein a plurality of reliability scores of right eyes andleft eyes pertaining to each of the plurality of registrants are storedin the storage, each of the plurality of reliability scores representingease of identification between eyes of others, and wherein the at leastone processor is further configured to execute the instructions to:specify the authentication target based on the verification score;calculate a weighted verification score by weighting the verificationscore with a reliability score with respect to the specifiedauthentication target acquired from the storage; and authenticate theauthentication target using the weighted verification score instead ofthe verification score.
 5. The authentication device according to claim4, wherein the at least one processor calculates the weightedverification score using the higher of the reliability score of the lefteye and reliability score of the right eye with respect to theauthentication target.
 6. The authentication device according to claim1, wherein the first image includes a whole body of the authenticationtarget, and wherein the at least one processor extracts, as the firstbiological information of the authentication target, information on ahuman shape or a gait from a first image.
 7. An authentication methodcomprising: by at least one processor, extracting first biologicalinformation of an authentication target from a first image, theauthentication target being moving in a predetermined direction in avideo of a predetermined area, the first image being an image bycapturing the authentication target; extracting, as candidateinformation of the authentication target, one or more sets of registrantinformation from a storage by performing a first authentication usingthe first biological information, the storage storing a plurality ofsets of registrant information about a plurality of registrants to beauthenticated; holding the extracted candidate information temporarily;extracting second biological information of the authentication targetfrom a second image, the second biological information being differenttype from the first biological information, the second image being animage by capturing the authentication target moving in the predetermineddirection after the first image is captured; determining, as a secondauthentication, whether to authenticate the authentication target bycomparing the second biological information and one or more sets ofbiological information of being included in one or more sets ofcandidate information and the same type as the second biologicalinformation, the second authentication being an authentication processwith higher accuracy than the first authentication; and discarding theheld candidate information when the authentication target does not movein the predetermined direction between time the first image is capturedand time the second image is captured.
 8. The authentication methodaccording to claim 7, wherein the second authentication is irisauthentication.
 9. The authentication method according to claim 8,wherein, in the second authentication, the at least one processorcalculates a verification score with respect to the authenticationtarget by comparing characteristic information calculated from an irisof an eye of the authentication target in the second image with one ormore sets of characteristic information about irises of eyes included inone or more sets of candidate information; authenticates theauthentication target using the calculated verification score; andoutputs a authentication result.
 10. The authentication method accordingto claim 9, wherein a plurality of reliability scores of right eyes andleft eyes pertaining to each of the plurality of registrants are storedin the storage, each of the plurality of reliability scores representingease of identification between eyes of others, and wherein theauthentication method further includes: by the at least one processor,specifying the authentication target based on the verification score;calculating a weighted verification score by weighting the verificationscore with a reliability score with respect to the specifiedauthentication target acquired from the storage; and authenticating theauthentication target using the weighted verification score instead ofthe verification score.
 11. The authentication method according to claim10, further comprising by the at least one processor, calculating theweighted verification score using the higher of the reliability score ofthe left eye and reliability score of the right eye with respect to theauthentication target.
 12. The authentication device according to claim7, wherein the first image includes a whole body of the authenticationtarget, and wherein the at least one processor extracts, as the firstbiological information of the authentication target, information on ahuman shape or a gait from a first image.
 13. A non-transitory storagemedium storing a computer program for causing a computer to implement:extracting first biological information of an authentication target froma first image, the authentication target being moving in a predetermineddirection in a video of a predetermined area, the first image being animage by capturing the authentication target; extracting, as candidateinformation of the authentication target, one or more sets of registrantinformation from a storage by performing a first authentication usingthe first biological information, the storage storing a plurality ofsets of registrant information about a plurality of registrants to beauthenticated; holding the extracted candidate information temporarily;extracting second biological information of the authentication targetfrom a second image, the second biological information being differenttype from the first biological information, the second image being animage by capturing the authentication target moving in the predetermineddirection after the first image is captured; determining, as a secondauthentication, whether to authenticate the authentication target bycomparing the second biological information and one or more sets ofbiological information of being included in one or more sets ofcandidate information and the same type as the second biologicalinformation, the second authentication being an authentication processwith higher accuracy than the first authentication; and discarding theheld candidate information when the authentication target does not movein the predetermined direction between time the first image is capturedand time the second image is captured.
 14. The non-transitory storagemedium according to claim 13, wherein the second authentication is irisauthentication.
 15. The non-transitory storage medium according to claim14, wherein the computer program for causing a computer to implement: inthe second authentication, calculating a verification score with respectto the authentication target by comparing characteristic informationcalculated from an iris of an eye of the authentication target in thesecond image with one or more sets of characteristic information aboutirises of eyes included in one or more sets of candidate information;authenticating the authentication target using the calculatedverification score; and outputting a authentication result.
 16. Thenon-transitory storage medium according to claim 15, wherein a pluralityof reliability scores of right eyes and left eyes pertaining to each ofthe plurality of registrants are stored in the storage, each of theplurality of reliability scores representing ease of identificationbetween eyes of others, and wherein the computer program for causingfurther a computer to implement: specifying the authentication targetbased on the verification score; calculating a weighted verificationscore by weighting the verification score with a reliability score withrespect to the specified authentication target acquired from thestorage; and authenticating the authentication target using the weightedverification score instead of the verification score.
 17. Thenon-transitory storage medium according to claim 16, wherein thecomputer program for causing further a computer to implement:calculating the weighted verification score using the higher of thereliability score of the left eye and reliability score of the right eyewith respect to the authentication target.
 18. The authentication deviceaccording to claim 13, wherein the first image includes a whole body ofthe authentication target, and wherein the computer program for causingfurther a computer to implement: extracting, as the first biologicalinformation of the authentication target, information on a human shapeor a gait from a first image.